I figured I would add another voice to the growing list of people with this issue. I am not a previous XPS owner, so I don't have any experience with the prior issues of this laptop. I am not a gamer first, but do play casually in some games. I don't expect high performance, but do expect consistent playability. I recently returned the MSI PS63 Modern with the same GPU. I successfully played both Subnautica and Black Mesa on that laptop with no modifications and had an excellent experience with no slowdowns; that laptop is also extremely thin. I returned it for the XPS due to the poor screen and subpar build quality. The 4K LED on this XPS is absolutely gorgeous.

I have tried many of the suggestions posted in other threads with no change. In both Subnautica and Black Mesa, the GPU throttles itself back to 300Mhz every few minutes. Due to the age of Black Mesa's engine, this results in an FPS of 30. In Subnautica, the FPS drop from a consistent 60 to sub 15. This occurs without GPU temps hitting 75, it sometimes occurs around 70. CPU does not throttle extensively.

Things I've tried.

Undervolted with XTU to -125.

Disabled Turbo Boost is the BIOS.

Set the profile to maximum performance (or whatever) in the Dell Power Manager.

Disabled all power saving features in the Intel display settings panel.

Lowering graphics quality settings in both games to the medium, although not the lowest.

Uninstalled the Intel thermal platform (forgot exact name). This made no difference so I re-installed from Dell's website.

Updated all drivers and BIOS to newest.

Updated GPU drivers to newest with NVIDIA Experience (the FPS drop was occurring before install Experience).

It doesn't make sense to me that a laptop this powerful throttles on a game based on an engine from 2004. Obviously they've tweaked and improved the engine since then, but still. My 8 year old HP Envy with discrete graphics sustained OK frame rates in Black Mesa with no issues.

Also, to those that say this isn't a gaming laptop: Would this not impact professionals working in 3D or potentially video as well? Games are not the only thing that can push a GPU.

[edit]Update 1: After an 1 1/2 hours on the phone with Dell support, they are blaming the GTX 1650 and are sending an on-site tech. They offered this or an advance replacement. I chose the on-site because they estimated a 1-2 day turnaround vs 7 - 10 days. I'm a little suspect of this since it's such a new laptop. I worry that the local tech won't receive parts that quickly. The Dell rep did test something that I forgot to myself, disabling the Intel graphics in device manager entirely. Interestingly, games refuse to use the dedicated graphics in this instance. The NVIDIA control panel also doesn't launch. Is this to be expected due to how the switchable graphics drivers work?

I'll update this thread as the repair progresses. We'll see if it actually is hardware.[/edit]

[edit]Update 2 (7/17/2019): A very friendly on-site tech replaced the laptop's motherboard. He mentioned that the factory paste job was quite good. I immediately tested with Subnautica after the replacement and the issue is still present. This time I noticed that the GPU was allowed to hit higher temps (76 - 80). It wasn't until temps stabilized at 70 - 74 that the frequency dropped to 300Mhz. The tech saw the issue occur as well and called his field tech line to inform Dell that the issue was still present. The field tech line simply told him that the customer (me) would need to call support again.[/edit]

I had a similar issue with an older XPS laptop. The CPU was locked to 0.9Ghz and it wouldn't go any faster. The solution was simply to take off the bottom cover, disconnect the battery for 15 minutes and the reconnect it. After booting back up the laptop behaved normally again (CPU speed going up and down as required), and the problem hasn't come back in over 18 months. So definitely give that a go. I thought it sounded ridiculous too, but it worked for me.

In my case, the CPU seems to be working fine. It moves around between 2.5 and 3.5 - 4Ghz as needed. The GPU also moves around, but encounters some sort of temp criteria (or something else) and its frequency crashes to 300Mhz, making modern games nearly unplayable.

We recommend keeping all the drivers and firmware updated from the Dell support assist tool.
Did you make any hardware or software changes to the system recently?
Does the issue happen on multiple games/applications or just specific games?
Are those games played online?
Does the computer work fine while on regular tasks?
Do rest of the applications work fine?
Is the Discrete GPU showing up in the Device Manager ?
What is the BIOS and graphics driver verion installed on the laptop?

Here are a few troubeshooting steps that you can follow:

Is the Discrete GPU showing up in the Device Manager ?

Click on the Start button

Type in devmgmt.msc by using the Run command or Device Manager in the Search field

That's odd that they didn't offer to fix or replace the laptop. The rep I was working with had me test a few games while remoted to the computer after different fix attempts. After they exhausted their options, they gave me the option of shipping an advance replacement or the on-site tech.

Replacement mobo did not fix the issue. I did finally try the GPU undervolt from that other post on Reddit. Along with a -.125 CPU undervolt, a max TDP of 15W and disabling short power max, I was able to play consistently for over 20 minutes.

Hi,
This is to check if you are still facing throttling issues. If yes, please send a private message with system Service Tag for us to forward it to our product engineering team and we shall try our best to fix this at the earliest.
KK

I have gone back and forth with Dell support on the phone. Two days ago I received a new BIOS update that fixed this issue 100% for me. I am now able to have Intel Boost and I don't have to have afterburner running in order to play PUBG at 60 fps on Medium-high settings.

A good chunk of my issues with the Gigabytes and MSIs is build. My biggest pet peeve with the MSI PS63 (other than the screen) was that it creaked when you picked it up from the palm rest corners. The build of the XPS appears to be much better, and that's something I value.